<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .btnBox {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            display: flex;
        }

        .btnBox button {
            margin: 10px;
            background-color: white;
            width: 50px;
            height: 50px;
            border-radius: 50%;
            box-shadow: 0 1px 3px 1px #666666;
            border: none;
            transition: .3s;
            position: relative;
        }

        .btnBox button:hover {
            background-color: #999999;
            cursor: pointer;
        }

        .btnBox button:before {
            position: absolute;
            top: 50%;
            transform: translate(-50%, -50%) rotate(45deg);
            content: '';
            display: block;
            width: 15px;
            height: 15px;
            border: 4px solid #bbbbbb;
            transition: .3s;
        }

        .btnBox button:hover:before {
            border-color: white;
        }

        .btnBox .prev:before {
            border-top: none;
            border-right: none;
            left: 60%;
        }

        .btnBox .prev:hover:before {
            left: 40%;
        }

        .btnBox .next:before {
            border-left: none;
            border-bottom: none;
            left: 40%;
        }

        .btnBox .next:hover:before {
            left: 60%;
        }


        .btnBox button:after {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            content: '';
            display: block;
            width: 0;
            height: 4px;
            background-color: #bbbbbb;
            transition: .3s;
        }

        .btnBox button:hover:after {
            background-color: white;
            width: 26px;
        }
    </style>
</head>
<body>
<div class="btnBox">
    <button class="prev"></button>
    <button class="next"></button>
</div>
</body>
</html>